Nope...it's just a random animation that your Tama does...sometimes it will even press its face against the screen if you press C when nothing is highlighted. Totally normal. You will know that your Tama is dying if it's standing in the middle of the screen with a pained/sad look on its face. There will be a sick skull right above your Tama's head and you won't be able to press any buttons. Hope this helps!